Physicochemical analysis are carried out on samples of torrefied pine obtained at 260°C in inert atmosphere. Gaseous effluents which evolve in the first moments of the pyrolysis as well as liquid phase are analyzed by gas-chromatography. It appears from the solid analysis, that the chemical structure of pine is strongly altered by the process. The roasted wood exhibits particular properties: pronounced hydrophobic character, improved energetic power, a noticeable increase in ash content, a decrease of the volatile components and a decrease of those extracted by neutral solvents. It is shown that the more substantial change occurs at the beginning of heating.